add<KQKR>("KQKR");
add<KNNKP>("KNNKP");
- add<KNPK>("KNPK");
- add<KNPKB>("KNPKB");
add<KRPKR>("KRPKR");
add<KRPKB>("KRPKB");
add<KBPKB>("KBPKB");
&& relative_rank(weakSide, pos.square<KING>(strongSide)) >= RANK_4
&& relative_rank(weakSide, rsq) == RANK_3
&& ( pos.pieces(weakSide, PAWN)
- & pos.attacks_from<KING>(kingSq)
- & pos.attacks_from<PAWN>(rsq, strongSide)))
+ & attacks_bb<KING>(kingSq)
+ & pawn_attacks_bb(strongSide, rsq)))
return SCALE_FACTOR_DRAW;
return SCALE_FACTOR_NONE;
// the corner
if ( rk == RANK_6
&& distance(psq + 2 * push, ksq) <= 1
- && (PseudoAttacks[BISHOP][bsq] & (psq + push))
+ && (attacks_bb<BISHOP>(bsq) & (psq + push))
&& distance<File>(bsq, psq) >= 2)
return ScaleFactor(8);
}
if ( ksq == blockSq1
&& opposite_colors(ksq, wbsq)
&& ( bbsq == blockSq2
- || (pos.attacks_from<BISHOP>(blockSq2) & pos.pieces(weakSide, BISHOP))
+ || (attacks_bb<BISHOP>(blockSq2, pos.pieces()) & pos.pieces(weakSide, BISHOP))
|| distance<Rank>(psq1, psq2) >= 2))
return SCALE_FACTOR_DRAW;
else if ( ksq == blockSq2
&& opposite_colors(ksq, wbsq)
&& ( bbsq == blockSq1
- || (pos.attacks_from<BISHOP>(blockSq1) & pos.pieces(weakSide, BISHOP))))
+ || (attacks_bb<BISHOP>(blockSq1, pos.pieces()) & pos.pieces(weakSide, BISHOP))))
return SCALE_FACTOR_DRAW;
else
return SCALE_FACTOR_NONE;
}
-/// KNP vs K. There is a single rule: if the pawn is a rook pawn on the 7th rank
-/// and the defending king prevents the pawn from advancing, the position is drawn.
-template<>
-ScaleFactor Endgame<KNPK>::operator()(const Position& pos) const {
-
- assert(verify_material(pos, strongSide, KnightValueMg, 1));
- assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
-
- // Assume strongSide is white and the pawn is on files A-D
- Square pawnSq = normalize(pos, strongSide, pos.square<PAWN>(strongSide));
- Square weakKingSq = normalize(pos, strongSide, pos.square<KING>(weakSide));
-
- if (pawnSq == SQ_A7 && distance(SQ_A8, weakKingSq) <= 1)
- return SCALE_FACTOR_DRAW;
-
- return SCALE_FACTOR_NONE;
-}
-
-
-/// KNP vs KB. If knight can block bishop from taking pawn, it's a win.
-/// Otherwise the position is drawn.
-template<>
-ScaleFactor Endgame<KNPKB>::operator()(const Position& pos) const {
-
- assert(verify_material(pos, strongSide, KnightValueMg, 1));
- assert(verify_material(pos, weakSide, BishopValueMg, 0));
-
- Square pawnSq = pos.square<PAWN>(strongSide);
- Square bishopSq = pos.square<BISHOP>(weakSide);
- Square weakKingSq = pos.square<KING>(weakSide);
-
- // King needs to get close to promoting pawn to prevent knight from blocking.
- // Rules for this are very tricky, so just approximate.
- if (forward_file_bb(strongSide, pawnSq) & pos.attacks_from<BISHOP>(bishopSq))
- return ScaleFactor(distance(weakKingSq, pawnSq));
-
- return SCALE_FACTOR_NONE;
-}
-
-
/// KP vs KP. This is done by removing the weakest side's pawn and probing the
/// KP vs K bitbase: If the weakest side has a draw without the pawn, it probably
/// has at least a draw with the pawn as well. The exception is when the stronger